Training Magic
by Leikar
Summary: A young Sans went to train his magic after a small accident with lab susbtances. But there's nothing to worry about, right?


**Training magic**

It was a cold day in the forest of Snowdin, and it had snowed last night. That wasn't exactly infrequent in that part of the Underworld, though. However, the wind wasn't blowing; and that meant that it wouldn't probably snow again until afternoon at least. And that was perfect for Sans' plans. It had been a while since he had trained his magic, and was starting to feel _too_ energetic. It could be dangerous for monsters not to practice their magic on a regular basis.

The only problem with that forest was that there weren't many thins to practice magic on. Make a few leaves fall and fly around with the blue magic and hit the rocks with bones. But without an opponent to fight with, Sans couldn't improve much. It was fine, however. The child monster just wanted to play around. Papyrus usually joined him, but then they always ended up in a snowball fight rather than practicing their magic. It was really fun, but not exactly what they should be doing. So, in other to make sure that they would often train, they agreed to go alone to the forest from time to time. It wasn't a dangerous place, anyway.

But that day, Sans wasn't alone. There was a small froggit hopping around the place where he usually trained. The monster seemed lost, and jumped near Sans, looking for help.

"what's up" the young skeleton kneeled next to the froggit.

"I'm lost." the froggit was almost tearing, and obviously scared "There was a hole in the Ruins, and I wanted to see what was out there because the door is always closed, and the goat lady that lives there never opens it. So I went through the hole and explored the forest but now I'm lost. I wanna go home!" the monstter whimpered.

"the ruins, huh? i think i can help you then. follow me, pal." Sans smiled, reassuring the froggit. The lost monster jumped, hopeful; and they started walking. Sans told him that he was training to distract his companion a little. He knew froggits were nervous monsters, and if he started crying again, it would be more difficult to reach the door of the Ruins, despite how close they were.

However, when they got to the Ruins and found the hole where the froggit had come from, he refused to go. He wanted to help Sans with his training as a thanks, as long as they didn't go too far from the entrance. The skeleton accepted. Making rocks float with blue magic was a little boring after a while, and throwing bones trying to hit nothing was... useless.

* * *

"If you need help, you know where we are." Gaster told them, as always "Behave yourselves and have fun."

"DON'T WORRY, DAD. I,THE GREAT PAPYRUS, WILL TAKE CARE OF MY FRIEND AND MY BROTHER." the young skeleton shouted while Alphys waved shyly at the adult. Sans winked at his father and he nodded slightly. Despite being the youngest one, Sans was clearly the most mature of the three kids. Gaster knew he would keep the others out of trouble.

Gaster didn't have many co-workers, but he was glad that at least one of them had and brought his child at work too. He couldn't leave the brothers alone at home, even if he felt a little guilty the skeletons spent most of their time enclosed in one room of the lab. The children didn't seem to care, but he knew they would be better running around Snowdin's forest, not trapped in the lab. At least they could keep little Alphys company. She and her father lived in Hotland, and lava _was_ dangerous.

When Gaster exited the room, they played _Monsters and Humans_ : Papyrus protected his grinning brother from Alphys, the Terrible Human. They changed roles a few times, but got bored after a while. It was then when Alphys remembered seeing a cool book in one of the shelves on the next room. Even if they were not supposed to leave the playroom, the three of them had already explored more than half of the first floor. And since their old toys weren't as appealing to them as a new and unknown book, they agreed on going and check it.

Sans went out first and checked there were no adults near. The other followed him, with Papyrus at the end, who had the important duty of making sure no one would sneak up on them. They entered the room after the short walk through the corridor. There weren't any monsters working there and, from what they knew, that room wasn't frequented lately.

"Up there!" Alphys said, pointing at a shelve full of books over a table with some bottles, most of them empty. The skeleton brothers immediately saw the bright pink book among the dull grey and blue ones. Its contents may have not been interesting for the kids, but the difference of color was amusing enough. They agreed to use one chair to get it. But it wasn't high enough to reach the book, even for Papyrus, who was the tallest; and Sans climbed his shoulders. However, Papyrus' foot slipped and lost balance, making himself and his brother fall on the table. The sound of crashed bottles resonated over the room.

"Oh, no! Oh, no, no , no!" Alphys panicked. "Are you alright?"

"DON'T WORRY, WE'RE FINE." Papyrus replied while Sans nodded. Their bones were harder than skin ant they hadn't been cut. They only needed to clean up the broken glasses and the yellow and red substance two of the bottles have had and that now was splattered on their skulls. When they finished making sure everything was fine, cleaned, and they wouldn't be punished, they fled back to the playroom before someone started looking for them.

* * *

Sans couldn't sleep that night. The sheets were scattered through the room and he was squirming, unable to lie still. He was feeling restless, like he had too much energy. He tried running around his room for a while, but it barely helped. He went to the kitchen in silence to drink some water. The small walked helped, but it wasn't enough. He was sweating, but he was feeling fine. More than fine, in fact. The only problem seemed to be his nervousness, so he decided to go back to bed. He managed to sleep a couple of hours before waking up again.

Sans sighted, defeated by that strange insomnia that had overcome him for no reason. He got up and dressed, and left the house leaving a note so his father wouldn't be worried. The sun had already risen when he got to his training place near the Ruins. The froggit appeared after a while. They used to train together since the day they met. Sans never hurt badly the small monster, and he loved jumping around even higher thanks to the blue magic.

They warmed up before starting the training. Sans notice he was feeling better the more bones he summon, and realized that it had been a while since he last used his magic. Maybe he just needed to train. Sans still warned the froggit about his magic. The other monster happily hopped, not worried about it. Since they started training together, he had gained a lot of confidence. They stood in front of each other, prepared for the battle, and Sans moved his left arm to summon some blue bones under the froggit.

Sans knew something was wrong one instant later, but he could no longer stop the attack. His magic went through his body with a lot more force that it should have, to the point it was physically painful. His left eye started shining like the crystals in Waterfall and, suddenly, a huge spiky skull appeared out of nowhere and floated at his side for a second. Then it opened its mouth and shot a powerful laser towards the froggit. The poor monster didn't had time to react, and the attack obliterated him. Then, the skull disappear.

Sans almost passed out of exhaustion and pain. His legs didn't managed to keep him standing, and he fell to his knees. There was nothing in front of him but melted snow and a small pile of dust. That froggit has dead. And he had killed him.

The realization was the worst part. Sans didn't know how or what was happened, but the kid knew it was his fault. He managed to stand up, and run away. Shaking. Crying. Terrified.

* * *

His sudden burst into home almost managed make Gaster break his cup of tea. The adult looked at him from the coach, startled and worried, when he notice Sans' left eye. It was shining in a clearly unnatural way. Gaster hurried up and kneel next to Sans, whose shaking and crying had gotten worse. He was terrified.

"Sans! What's wrong? What happened?" his father asked, hugging Sans. The scientist felt stupid for a second. Sans was clearly confused, while the scientist knew exactly what was going on. What he didn't know was... how. The bottles of Determination and Magic Enhancer were in his lab, and Sans was always playing with Alphys and Papyrus. They couldn't have possibly...

"i'm sorry! i'm sorry! i'm sorry!" the skeleton kid started crying in panic, confirming Gaster's theory. He could feel the energy building up inside Sans body. There was no time for that. They had to get to the lab immediately, so he grabbed the kid, got out of the house and run towards the River Person. Sans unintentionally summoned up another skull that blasted towards the sky, but they already were far enough the town, so no one should have seen them. Except the River Person, but they didn't care.

"To Hotland! Now!" Gaster shouted, and the boat started running as fast as possible over the river.

Determination was bad enough, but the Magical Enhancer was proving to be worse for Sans than anything else. Such a powerful magic in such a small and young body was too much for him. Sans was exhausted and barely conscious, yet his body insisted in blasting powerful lasers of magic in an attempt to discharge the seemly endless excess of magical energy. If things kept going like that, Sans would die after a few more blasts. They needed to get to the lab and stabilize him.

Fortunately, the lab was empty. It was holiday, but Gaster knew that some of his coworkers worked on those days if the experiments demanded it. He himself had sometimes done it. He run towards the room with the magical stabilizer with Sans in his arms, and turned it on. The machine looked like a huge test tube with a control panel that was showing some data.

Gaster pressed some buttons and hurriedly put Sans inside the tube. He was charging another blast and Gaster wasn't sure Sans would be able to survive it. The machine started working, and magical electricity started flowing inside the tube. Sans didn't feel pain, but but the machine was manipulating his internal magic, and it was extremely uncomfortable. The skeleton kid squirmed and groaned, trying to stop the sensation while his magic burned him from the inside. Gaster watched with apprehension until the machined finished. Then, Sans looked, and was, exhausted, but also better than before. He even doze off before Gaster took him out the machine.

The adult skeleton carried Sans in his arms towards the playroom. Occasionally, Gaster had so much work they had to sleep in the lab, so he had brought some mattress and sheets. Alphys loved when her father let her stay there for the night and the three kids had a sleepover. Gaster tucked Sans in bed and called home. Papyrus had been playing in Waterfall when Sans arrived home, but he surely would have gone back and got worried seeing the place was empty. Gaster told him he had had some sudden work and apologized for leaving without notifying him. The kid assured him it was fine, and Gaster told him to go to the shop and buy lunch there.

There was one thing Gaster had to check, so he went to the room where the Determination and Magical Enhancers should be. Of course, they weren't there. Nor there weren't many other empty bottles. There _were_ many crystals on a near trash can. Gaster sighted. He couldn't say that was only Sans' fault. That was certainly the last time he would leave something as dangerous lying around on a table. He went back to the playroom, and waited until Sans woke up. When he did, he still seemed tired and scared, but a lot better than before. Gaster sit next to him and assured him that he wasn't angry. That was a lie, but he had been stupid thinking he would never sneak out the room. For the power of Souls, they were _kids_!

"I need to know what happened." Gaster said kindly, trying to hide his anger.

Sans stiffed. He felt guilty and knew his father was angry, no matter how many times he denied it, but he told him about their little adventure. Knowing that Papyrus had been spilled with the substances worried Gaster, but the child's voice had seemed fine when he phoned him. Given that his body was bigger and more mature than Sans', the scientist figured the symptoms would take more days to show, and they would be probably less aggressive. Gaster took a mental note to keep an eye on Papyrus from that day on.

"Sans, listen to me, because this is important." he looked at his son calmly, but seriously. The young skeleton looked up, feeling his nervousness building up again in anticipation. "What your brother and you touched was 'Determination' and a Magical Enhancer. Determinations is something humans have but monsters don't. We are still unsure of its effects on monsters, but the quantity of that bottle was very little, so I doubt it affected you or will affect your brother much. I think it's more likely that the Determination emphasized the Magical Enhancer effects. Your magical power grew too much in too little time, and your body couldn't bear it. That's what happened to you, Sans."

Gaster paused, letting his son absorb the information.

"That machine helped your body assimilate your increased magic. You will need to use it again, at least until your body stops growing up. It will be the same for your brother; I'll call him tomorrow and tell him to come here."

Gaster made a small pause, staring seriously at his son. He wasn't going to like his next words.

"And you cannot use your magic again" he said.

Sans stared at him, astonished. His father couldn't be possibly prohibiting him to use magic, could he? Magic was everything for a monster. Their way to express themselves without boundaries. Their bodies. Their souls. Their essences.

"Not until you are an adult and you are completely stable." his father continued "Your magic is to powerful for you right now, Sans. If you use it, your body won't be able to stand it. You can use the Magic Stabilizer machine to deal with the excess of magic due to the lack of practice. But don't summon up bones or use your blue magic until you get better, because you will not survive. Understood, Sans?"

Sans nodded, tense and scared. Gaster hugged his son.

"Don't worry, Sans, you will be fine. And Papyrus will too. Go to sleep again, you need to rest."

But Sans hugged him back and refused to let him go, bursting out in tears. That little froggit was dead. Nothing would be fine again.


End file.
